In some types of partial middle ear implantable (P-MEI) or total middle ear implantable (T-MEI) hearing aid systems, sounds produce mechanical vibrations which are transduced by an electromechanical input transducer into electrical signals. These electrical signals are in turn amplified and applied to an electromechanical output transducer. The electromechanical output transducer vibrates an ossicular bone in response to the applied amplified electrical signals, thereby improving hearing.
Such electromechanical input and output transducers should be proportioned to provide convenient implantation in the middle ear. Low power consumption transducers are also desired for use with a limited longevity implanted battery as a power source. The electromechanical input transducer should have high sensitivity, gain, linearity, and a wide dynamic range in producing electrical signals from a sensed mechanical vibration. The electromechanical output transducer should have low power consumption in producing mechanical vibrations from an applied electrical input signal.